Proxy Mines can vanish if landed in an area with limited height.

[PixelTwitch]

EDIT: On closer inspection it appears they vanish on hitting peoples heads.

//youtu.be/KvP6bj0uYNg

[PixelTwitch]

Added Video:

[video]https://youtu.be/KvP6bj0uYNg[/video]